Pressure-indicator for air-brake apparatus



H. H. WESTINGHOUSE. PRESSURE INDICATOR FOR AIR BRAKE APPARATUS.

N0.42 1,6 4l. Patented Feb. 18, 1890.

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azu- I NITED STATES ATENT smear HENRY HERMAN WESTINGHOUSE, OF PIT'ISBURG, PENNSYLVANIA.

PRESSURE-INDICATOR FOR Ann-sums APPARATUS.

SPlilCIFICATIQN-forming part of LettersPatent No. 421,641, dated February 18, 1890.

Application filed August 29, 1889. Serial No. 322,359 (No model),

To all whom it may concern.-

Be it known that I, llnxnr HERMAN Wnsr INGl-IOUSE, a citizen of the United States, re siding at littsburg, in the county of Allegheny and State of Pennsylvania, have invented or discovered a certain new and use fnl Improvement in lressnrc'lndicators for Air-Brake Apparatus,of which improvement the following is a specification.

In the operation of air-brake apparatus of the automatic type it is desirable and usual in practice to constantly maintain a higher pressure in the main reservoir, in which air is compressed by theipump, than in the train or brake pipe, from which the compressed air is delivered to the brake-cylinders for actuating the brakes, such difference of pressure being increased during their application, and it is important that the engineer should at all times be in position to immediatelyascertain the varying pressures in the reservoir and brake-pipe and readily determine whether the same are normal in degree and relation.

The object of my invent-ion is to provide simple and convenientmeans for such ascertainment; and to this end my invention, generally stated, consists in the combination, with a main air-reservoir and brake-pipe, of an engineers valve adapted to regulate a difference of pressures in said reservoir and pipe, and a pressure-indicator connected to said reservoir and pipe, respectively, and adapted to indicate upon a dial the (litterence of pressures therein.

The improvement claimed is hereinafter fully set forth.

In the accompanying drawings, Figure 1 is a view in elevation of so much of an airbrake apparatus as is necessary to illustrate the application of my invention; and Fig. 2, a perspective view, partly in section and on an enlarged scale, of the indicator detached.

My invention is herein shown as applied in connect-ion with an automatic air-brake appa ratus of the standard construction, in which air under pressure is applied from a main air-reservoir l to a train or brake pipe 4, and thence to an auxiliary reservoir 16 through a triple valve 17, the application or the brakes being effected by a reduction of pressure in the brake-pipe 4 by the engineers valve 3, which controls communication between the the brake-pipe to the brake-cylinder, although from the character of such apparatus its ad vantage is not to an equal degree available.

In the practice of my invention I provide a pressureindicator 6, consisting of a suitable casing, in which are i'nclosed two separate and independent pressure-gage mechanisms 9 and 10, the registrations of which are indicated upon a single-dial plate 12. In the instance illustrated said mechanisms are curved-tube gages of the Bourdon type provided with supply-nozzles 14 and 15, which are connected, respectively, with the main reservoir 1 and with the brake-pipe 4 by pipes 7 and 8. As shown in the drawings, the pipe 7 leads into thepipe 2, which connects the engineers brake-valve 3 with the main reservoir, and the pipe 8 into the brake-pipe passage of the engineers valve; but such or any special location of the supply ends of the pipes 7 and 8 is not material, as both maybe led into the casing of the engineers valve on opposite sides of the valve or into the main reservoir and brake-pipe connections thereof, respectively, as convenience or the dis cretion of the constructer may dictate. The hands or indexes 13 and 11, which are actuated through suitable gearing by the moveble ends of the gages 9 and 10, respectively, are fitted to traverse concentrically and independently over the outside of the dial 12, upon which is marked a segmental series of figures, which serve to indicate by the p'osi tion relatively thereto of the indexes 13 and 11, respectively, the respective pressures which are maintained in the main reservoir and in the brake-pipe. The indenes l3 and 11 are preferably of difierent colors or are dilferently shaped,in order to enable them to be plainly distinguished one from the other.

The registration of both reservoir and brake-pipe pressure upon a single dial, as above described, enables the engineer to observe both pressures as from time to time varied with greater quickness and accuracy than is possible where separate gages are emp10yed,:tud to discern at a. glance whether their normal relation of difference is maintained or is varied to any substantial degree.

I cia'im as my invention and desire to secure by Letters Patent-- In an sir-brake apparatus, the combine tion of a main air-reservoir, a brakepipe, an

engineers valve connected to said reservoir and brake-pipe and adapted to regulate 2t difference of pressures therein, and it pressureindicator communicating with the main ztirreservoir and the braEe-pipe and adapted to register upon a, single dial the difference of pressures therein, substantially as set forth. In testimony whereof I have hereunto set my hand.

HENRY HERMAN /ESTI'EGHOUr-it Witnesses:

J. SNOWDEN BELL, H. J. WEBsTER. 

